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RET proto-oncogene mutation analysis in a pedigree with multiple endocrine neoplasia 2A
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作者 张劲 《外科研究与新技术》 2011年第4期260-261,共2页
Objective To discuss clinical diagnosis and treatment of multiple endocrine neoplasia ( MEN) 2A,and report the mutation of RET proto-oncogene in a pedigree of three patients with MEN 2A. Methods Bilateral adrenalectom... Objective To discuss clinical diagnosis and treatment of multiple endocrine neoplasia ( MEN) 2A,and report the mutation of RET proto-oncogene in a pedigree of three patients with MEN 2A. Methods Bilateral adrenalectomy was performed on two of the three 展开更多
关键词 RET proto-oncogene mutation analysis in a pedigree with multiple endocrine neoplasia 2A
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Clinical and gene mutation studies on a Chinese pedigree with glucocorticoid-remediable aldosteronism
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作者 丁伟 刘礼斌 +2 位作者 胡仁明 许曼音 陈家伦 《Chinese Medical Journal》 SCIE CAS CSCD 2002年第7期979-982,142-143,共4页
OBJECTIVE: To report the clinical characteristics, biochemical profiles, diagnosis and treatment of one Chinese pedigree with glucocorticoid-remediable aldosteronism (GRA) and to study its molecular mechanism. METHODS... OBJECTIVE: To report the clinical characteristics, biochemical profiles, diagnosis and treatment of one Chinese pedigree with glucocorticoid-remediable aldosteronism (GRA) and to study its molecular mechanism. METHODS: Plasma and urinary aldosterone, cortisol and plasma renin activities were dynamically tested and diagnostic therapy with dexamethasone was undergone in 3 affected subjects. Long-distance PCR as well as DNA sequencing were applied to detect the fusion gene in this pedigree. RESULTS: In this GRA pedigree, there were 4 affected subjects who had hypertension, hypokalemia and low basic and provoked renin activity. Three patients were given dexamethasone treatment, and had a significant decrease in plasma aldosterone concentrations (PACs) (from 192 +/- 9 ng/L to 87 +/- 7ng/L, P 展开更多
关键词 mutation Adult ALDOSTERONE CORTICOTROPIN Female GLUCOCORTICOIDS Humans HYPERALDOSTERONISM pedigree Research Support Non-U.S. Gov't
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Revisiting the Evolutionary History of Pigs via De Novo Mutation Rate Estimation in A Three-generation Pedigree
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作者 Mingpeng Zhang Qiang Yang +1 位作者 Huashui Ai Lusheng Huang 《Genomics, Proteomics & Bioinformatics》 SCIE CAS CSCD 2022年第6期1040-1052,共13页
The mutation rate used in the previous analyses of pig evolution and demographics was cursory and hence invited potential bias in inferring evolutionary history.Herein,we estimated the de novo mutation rate of pigs as... The mutation rate used in the previous analyses of pig evolution and demographics was cursory and hence invited potential bias in inferring evolutionary history.Herein,we estimated the de novo mutation rate of pigs as 3.6×10-9 per base per generation using high-quality whole-genome sequencing data from nine individuals in a three-generation pedigree through stringent filtering and validation.Using this mutation rate,we re-investigated the evolutionary history of pigs.The estimated divergence time of~10 kiloyears ago(KYA)between European wild and domesticated pigs was consistent with the domestication time of European pigs based on archaeological evidence.However,other divergence events inferred here were not as ancient as previously described.Our estimates suggest that Sus speciation occurred~1.36 million years ago(MYA);European wild pigs split from Asian wild pigs only~219 KYA;and south and north Chinese wild pigs split~25 KYA.Meanwhile,our results showed that the most recent divergence event between Chinese wild and domesticated pigs occurred in the Hetao Plain,northern China,approximately 20 KYA,supporting the possibly independent domestication in northern China along the middle Yellow River.We also found that the maximum effective population size of pigs was~6 times larger than estimated before.An archaic migration from other Sus species originating~2 MYA to European pigs was detected during western colonization of pigs,which may affect the accuracy of previous demographic inference.Our de novo mutation rate estimation and its consequences for demographic history inference reasonably provide a new vision regarding the evolutionary history of pigs. 展开更多
关键词 PIG De novo mutation rate Three-generation pedigree Evolutionary history Archaic migration
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Analysis of cardiac troponin C gene TNNC1 c. G175C mutation in a Chinese pedigree with familial hypertrophic cardiomyopathy and the correlation between genotype and phenotype
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作者 邢晓博 《China Medical Abstracts(Internal Medicine)》 2017年第1期30-31,共2页
Objective To investigate the genotype-phenotype correlation in Chinese familial hypertrophic cardiomyopathy(HCM)focusing on the cardiac troponic C gene TNNC1 c.G175C mutation.Methods All family members of a Chinese pe... Objective To investigate the genotype-phenotype correlation in Chinese familial hypertrophic cardiomyopathy(HCM)focusing on the cardiac troponic C gene TNNC1 c.G175C mutation.Methods All family members of a Chinese pedigree with hypertrophic cardiomyopathy admitted in Third People’s Hospital of Qingdao 展开更多
关键词 HCM Analysis of cardiac troponin C gene TNNC1 c G175C mutation in a Chinese pedigree with familial hypertrophic cardiomyopathy and the correlation between genotype and phenotype gene
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Mitochondrial DNA A1555G mutation screening using a testing kit method and its significance in preventing aminoglycoside-related hearing loss 被引量:7
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作者 LIU Xin DAI Pu +10 位作者 HUANG Deliang YUAN Huijun LI Weiming YU Fei ZHANG Xin KANG Dongyang CAO Juyang YANG Weiyan HAN Dongyi JIN Zhengce GUAN Minxin 《Journal of Otology》 2006年第1期61-64,共4页
To report a new screening method for mitochondrial DNA 1555A→G mutation and the results of genotype analysis in 19 maternal inherited deafness pedigrees. Method Five hundred and forty-six non-syndromic neuro-sensory ... To report a new screening method for mitochondrial DNA 1555A→G mutation and the results of genotype analysis in 19 maternal inherited deafness pedigrees. Method Five hundred and forty-six non-syndromic neuro-sensory hearing loss patients were tested for 1555A→G mutation using a new compact testing kit, which allows clear distinction between wild type and 1555 A→G mutated mtDNAs. Results Nineteen subjects among the 546 patients (3.48%) were found to carry mtDNA A1555G mutation. The results were confirmed by sequencing in an ABI 3100 Avant sequencer. Conclusions Maternal inherited deafness families are a frequently seen in outpatient group. The detection of mtDNA 1555 A→G mutation with a low cost, ready to use detection kit is needed and suitable in China for large scale screening and preventive testing before usage of aminoglycoside antibiotics. 展开更多
关键词 ototoxic deafness maternal pedigree gene mutation prevention
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Solving chemical dynamic optimization problems with ranking-based differential evolution algorithms 被引量:3
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作者 Xu Chen Wenli Du Feng Qian 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第11期1600-1608,共9页
Dynamic optimization problems(DOPs) described by differential equations are often encountered in chemical engineering. Deterministic techniques based on mathematic programming become invalid when the models are non-di... Dynamic optimization problems(DOPs) described by differential equations are often encountered in chemical engineering. Deterministic techniques based on mathematic programming become invalid when the models are non-differentiable or explicit mathematical descriptions do not exist. Recently, evolutionary algorithms are gaining popularity for DOPs as they can be used as robust alternatives when the deterministic techniques are invalid. In this article, a technology named ranking-based mutation operator(RMO) is presented to enhance the previous differential evolution(DE) algorithms to solve DOPs using control vector parameterization. In the RMO, better individuals have higher probabilities to produce offspring, which is helpful for the performance enhancement of DE algorithms. Three DE-RMO algorithms are designed by incorporating the RMO. The three DE-RMO algorithms and their three original DE algorithms are applied to solve four constrained DOPs from the literature. Our simulation results indicate that DE-RMO algorithms exhibit better performance than previous non-ranking DE algorithms and other four evolutionary algorithms. 展开更多
关键词 dynamic optimization Differential evolution Ranking-based mutation operator Control vector parameterization
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SYSTEM IDENTIFICATION USING DYNAMIC GA BASED ON NUMERIC ENCODING
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作者 Yu Shouyi Peng Ying Zheng Xiaoming (College of Information Engineering, Central South University of Technology, Changsha 410083, China) 《Journal of Central South University》 SCIE EI CAS 1997年第2期128-131,共4页
A dynamic genetic algorithms based on numeric encoding is proposed and its application in system identification is discussed. Simulation shows that the introduction of both numeric encoding and dynamic mutation can ef... A dynamic genetic algorithms based on numeric encoding is proposed and its application in system identification is discussed. Simulation shows that the introduction of both numeric encoding and dynamic mutation can effectively improve the accuracy and speed of searching for the optimum. It also show that the improved Genetic algorithm can identify time delay and parameters of the plant at the same time and converge to globle optimization. 展开更多
关键词 GENETIC ALGORITHMS dynamic mutation OPERATOR system identification
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Are there fibroblast growth factor receptor 1 mutations in a Chinese Kallmann syndrome family?
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作者 Min Liu Yuling He Ping'an Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第20期1570-1574,共5页
The present study examined 58 members of a Kallmann syndrome family and investigated whether there are fibroblast growth factor receptor 1 (FGFR1) gene mutations in this family. Genomic DNA from the proband and fami... The present study examined 58 members of a Kallmann syndrome family and investigated whether there are fibroblast growth factor receptor 1 (FGFR1) gene mutations in this family. Genomic DNA from the proband and family members was subjected to PCR to amplify 18 exons of FGFR1, and the amplified products were sequenced to identify potential mutations. MRI of the olfactory bulb region was performed on suspected subjects. The patient and his father were diagnosed with Kallmann syndrome. A polymorphic site was found at 39542, with the proband and his parents being heterozygous (guanine + cytosine). However, healthy controls and the other members of this family were homozygous for guanine at this position. 展开更多
关键词 Kallmann syndrome pedigree investigation mutation fibroblast growth factor receptor 1
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Assessment of the forensic application of 50 Y-STR markers in a large pedigree
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作者 Yi Ye Yuran An +3 位作者 Yiwen Yang Hao Wu Yuzi Zheng Linchuan Liao 《Forensic Sciences Research》 CSCD 2022年第2期207-210,共4页
Short tandem repeats on the Y chromosome(Y-STRs),characterized by paternal inheritance,are valuable in forensic practice.Notably,the potential application of Y-STRs in pedigrees should be drawn upon,especially in Chin... Short tandem repeats on the Y chromosome(Y-STRs),characterized by paternal inheritance,are valuable in forensic practice.Notably,the potential application of Y-STRs in pedigrees should be drawn upon,especially in China’s surname-concentrated natural villages.The study focused on 50 Y-STRs,including 13 rapidly mutating(RM)Y-STRs that largely constitute the current Y-STR commercial kits,and determined the differences in these Y-STRs between branches in a large pedigree and the discriminatory power of these haplotypes in different units for male relatives.As indicated in the results,14 inconsistencies were observed at 9 Y-STRs between 10 father-son pairs.In addition,these 50 Y-STR haplotypes discriminated 10 out of 47 father-son pairs,106 of 148 cousin pairs,70 of 119 uncle-nephew pairs,17 of 39 brother pairs,and 14 out of 33 grandfather-grandson pairs in a large pedigree.The RM Y-STR set is able to differentiate close male relatives in a large pedigree. 展开更多
关键词 Forensic sciences forensic genetics Y-STR HAPLOTYPE rapid mutation pedigree
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Identification of a novel mutation in the FGF10 gene in a Chinese family with obvious congenital lacrimal duct dysplasia in lacrimo-auriculo-dento-digital syndrome
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作者 Hong-Yang Zhang Chun-Yan Zhang +8 位作者 Fei Wang Hai Tao Ya-Ping Tian Xi-Bin Zhou Fang Bai Peng Wang Jia-Yi Cui Min-Jie Zhang Li-Hua Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第4期499-504,共6页
AIM:To identify the pathogenic gene variant in a family with lacrimo-auriculo-dento-digital syndrome[LADD(MIM 149730)]showing congenital lacrimal duct dysplasia as the main clinical manifestation and lay the foundatio... AIM:To identify the pathogenic gene variant in a family with lacrimo-auriculo-dento-digital syndrome[LADD(MIM 149730)]showing congenital lacrimal duct dysplasia as the main clinical manifestation and lay the foundation for future research on the pathogenic gene.METHODS:Ophthalmological examinations,including slit-lamp biomicroscopy and lacrimal duct probing,and computed tomography dacryocystography(CT-DCG)were performed for all participants.The family pedigree was drawn,genetic features were analyzed,and the genomic DNA of the subjects was extracted.Pathogenic genes were screened via whole exome sequencing(WES)and confirmed using Sanger sequencing.RESULTS:Six patients belonged to this three-generation family,and their clinical manifestations included congenital nasolacrimal duct obstruction,congenital absence of lacrimal puncta and canaliculi,lacrimal fistulae,and limb deformities.This pattern indicates autosomal dominant inheritance.Diagnosis was based on the clinical characteristics of LADD syndrome,which presented in all the patients in this family.A novel frameshif t mutation in the FGF10 gene(NM_004465.1),c.234dup C(p.Trp79Leus*15),was identified in all patients via WES.The variant was confirmed by Sanger sequencing and classified as a“pathogenic mutation”according to the American College of Medical Genetics and Genomics(ACMG)variant interpretation guidelines.CONCLUSION:A novel frameshift mutation in the FGF10 gene is found in all patients.This finding helps this family with LADD syndrome receiving a more accurate clinical diagnosis and genetic counseling by extending the mutation range of the FGF10 gene. 展开更多
关键词 FGF10 gene frameshift mutation congenital lacrimal duct dysplasia LADD syndrome pedigree
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Unraveling the molecular mechanism of prion disease:Insights fromα2 area mutations in human prion protein
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作者 谈荣日 夏奎 +2 位作者 寻大毛 宗文军 余幼胜 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第12期657-665,共9页
Prion diseases are a class of fatal neurodegenerative diseases caused by misfolded prion proteins.The main reason is that pathogenic prion protein has a strong tendency to aggregate,which easily induces the damage to ... Prion diseases are a class of fatal neurodegenerative diseases caused by misfolded prion proteins.The main reason is that pathogenic prion protein has a strong tendency to aggregate,which easily induces the damage to the central nervous system.Point mutations in the human prion protein gene can cause prion diseases such as Creutzfeldt-Jakob and Gerstmann's syndrome.To understand the mechanism of mutation-induced prion protein aggregation,the mutants in an aqueous solution are studied by molecular dynamics simulations,including the wild type,V180I,H187R and a double point mutation which is associated with CJD and GSS.After running simulations for 500 ns,the results show that these three mutations have different effects on the kinetic properties of PrP.The high fluctuations around the N-terminal residues of helix 2 in the V180I variant lead to a decrease in hydrogen bonding on helix 2,while an increase in the number of hydrogen bonds between the folded regions promotes the generation ofβ-sheet.Meanwhile,partial deletion of salt bridges in the H187R and double mutants allows the sub-structural domains of the prion protein to separate,which would accelerate the conversion from PrPC to PrPSc.A similar trend is observed in both SASA and Rg for all three mutations,indicating that the conformational space is reduced and the structure is compact. 展开更多
关键词 prion protein mutationS MISFOLDING molecular dynamics simulations
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MD Simulations of the P53 oncoprotein structure: the effect of the Arg273→His mutation on the DNA binding domain
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作者 Kholmirzo Kholmurodov Ermuhammad Dushanov Kenji Yasuoka 《Advances in Bioscience and Biotechnology》 2011年第5期330-335,共6页
A comparative molecular dynamics (MD) simulation study was performed on the p53 oncoprotein to investigate the effect of the Arg273His (R273H) mutation on the p53→DNA Binding Domain (DBD). The two p53 dimer structure... A comparative molecular dynamics (MD) simulation study was performed on the p53 oncoprotein to investigate the effect of the Arg273His (R273H) mutation on the p53→DNA Binding Domain (DBD). The two p53 dimer structures of the wild-type and mutant Arg273His (R273H) were simulated with the same thermodynamic and environmental parameters. The obtained results demonstrate that the induced Arg273His mutation has a considerable effect on the p53→DNA close contact interaction and changes the picture of hydrogen formation. The Arg273His mutation, in some cases, destroys the existing native hydrogen bond, but, in other cases, forms a strong p53→DNA hydrogen bond, which is not proper for the native protein. The MD simulation results illustrate some molecular mechanism of the conformational changes of the Arg273His key amino acid residue in the p53→DNA binding domain, which might be important for the understanding of the physiological functioning of the p53 protein and the origin of cancer. 展开更多
关键词 Molecular dynamics Simulations P53 ONCOPROTEIN EFFECT of the R273H mutation DNA BINDING Domain
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一个遗传性凝血因子Ⅴ缺陷症家系的临床表型及分子致病机制研究
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作者 郭丽萍 董春霞 +2 位作者 王刚 王梅芳 杨林花 《中国实验血液学杂志》 CAS CSCD 北大核心 2024年第6期1822-1828,共7页
目的:探讨一个遗传性凝血因子Ⅴ缺陷症(coagulation factor V deficiency,FⅤD)家系的临床表型及分子致病机制。方法:采用一期法测定凝血因子Ⅱ、Ⅴ、Ⅶ、Ⅷ、Ⅸ、Ⅹ、Ⅺ、Ⅻ(FⅡ∶C、FⅤ∶C、FⅦ∶C、FⅧ∶C、FⅨ∶C、FⅩ∶C、FⅪ∶C、... 目的:探讨一个遗传性凝血因子Ⅴ缺陷症(coagulation factor V deficiency,FⅤD)家系的临床表型及分子致病机制。方法:采用一期法测定凝血因子Ⅱ、Ⅴ、Ⅶ、Ⅷ、Ⅸ、Ⅹ、Ⅺ、Ⅻ(FⅡ∶C、FⅤ∶C、FⅦ∶C、FⅧ∶C、FⅨ∶C、FⅩ∶C、FⅪ∶C、FⅫ∶C)、活化部分凝血活酶时间(activated partial thromboplastin time,APTT)及凝血酶原时间(prothrombin time,PT)进行表型鉴定;应用高通量外显子测序筛查全基因变异,Sanger测序验证F5基因可疑变异;利用Mutation-Taster、PolyPhen-2生物信息学软件预测变异致病性、ClustalX软件分析氨基酸保守性和PyMol软件模拟变异蛋白模型。结果:先证者PT、APTT明显延长,FⅤ∶C仅为5.45%,TT、FIB及其余凝血因子均无明显异常。其母亲、父亲、姐姐的PT、APTT均延长,FⅤ∶C不同程度减低。基因检测显示先证者F5第3号外显子存在c.286G>C(p.Asp96His)纯合错义变异,其父亲、母亲、姐姐均存在c.286G>C(p.Asp96His)杂合错义变异。生物信息学分析提示p.Asp96His为致病变异,相关的氨基酸位点在10个物种中高度保守。蛋白模拟显示,Asp96变异为His96后可导致原有氢键消失和距离改变,破坏了原有的氢键相互作用力,影响蛋白结构的稳定性。结论:F5第3号外显子c.286G>C(p.Asp96His)错义变异可能导致了先证者及家系成员FⅤ∶C的减低,也是引起凝血因子Ⅴ缺陷症的遗传学病因。 展开更多
关键词 遗传学凝血因子Ⅴ缺陷症 家系 错义变异
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Impact of Mutations on K-Ras-p120GAP Interaction
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作者 Chunxia Gao Leif A.Eriksson 《Computational Molecular Bioscience》 2013年第2期9-17,共9页
The K-Ras protein plays a key role in the signal transduction cascade. Certain mutations in K-Ras lead to a permanent “on” state which results in tumorigenesis due to failed interaction with the GTPase activating pr... The K-Ras protein plays a key role in the signal transduction cascade. Certain mutations in K-Ras lead to a permanent “on” state which results in tumorigenesis due to failed interaction with the GTPase activating protein (GAP). In this study, we examined the mutations E31N, D33N and D38N of K-Ras coupled and decoupled to wildtype GAP-334 and mutation K935N of GAP-334 coupled and decoupled to wildtype K-Ras, to illustrate the potential mechanism by which these mutants affect the interaction between the two proteins. We identify Tyr32 in the Ras Switch I region as a critical residue that acts as a gate to the GTP binding site and which needs to be “open” during Ras coupling with GAP to allow for insertion of GAP residue Arg789. This residue plays a vital role in stabilizing the transition state during GTP hydrolysis. The different mutations studied herein caused a reduced binding affinity, and the fluctuation of the Tyr32 side chain might hinder the insertion of Arg789. This may in turn be the cause of decreased GTP hydrolysis, and permanent “on” state of K-Ras, observed for these mutants. 展开更多
关键词 Ras Protein GTPase Activating Protein Molecular dynamics Simulations In Silico mutation Studies CANCER
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OPA1基因新发无义变异导致ADOA一家系临床表型和基因型分析
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作者 王莉红 王志立 +3 位作者 陈晓 魏嘉 陈慷 崔龙江 《中华实验眼科杂志》 CAS CSCD 北大核心 2024年第10期932-937,共6页
目的分析常染色体显性遗传性视神经萎缩(ADOA)一家系的临床表型及基因型。方法采用家系调查研究方法,纳入2023年7-10月在河南省立眼科医院就诊的中国河南地区汉族ADOA一家系2代4名成员,包括2例患者。详细询问患者及其家系成员病史,并进... 目的分析常染色体显性遗传性视神经萎缩(ADOA)一家系的临床表型及基因型。方法采用家系调查研究方法,纳入2023年7-10月在河南省立眼科医院就诊的中国河南地区汉族ADOA一家系2代4名成员,包括2例患者。详细询问患者及其家系成员病史,并进行全面的眼科检查,包括视力、视野、眼底、视网膜电图(ERG)、视觉诱发电位(VEP)、光学相干断层扫描;同时进行听力、肌电图及颅脑磁共振检查以明确是否伴有全身异常。收集该家系4名成员的外周血,对先证者进行全外显子组测序,其他成员采用Sanger测序验证。对新发现的变异位点进行致病性和蛋白结构分析。结果先证者女,15岁,左眼视力下降4年,双眼视神经萎缩,双眼黄斑区中心凹厚度稍变薄,神经节细胞复合体层厚度局部轻度变薄,VEP各波呈低振幅改变,部分视野缺失;全身检查未见明显听力障碍和肌张力异常。先证者母亲视神经部分区域萎缩,双眼黄斑区中心凹厚度稍变薄,VEP检查未见明显异常,ERG轻度异常。全外显子组测序结果显示,先证者及其母亲OPA 1基因外显子6出现杂合无义变异c.676C>T(p.Gln226Ter),该变异位点在HGMD数据库未见报道,千人基因组和gnomAD数据库未见收录,其可导致226位谷氨酰胺处发生提前终止。蛋白结构分析显示,OPA1蛋白p.Gln226Ter可造成蛋白与周围残基相结合的氢键改变,进而导致蛋白功能改变。根据ACMG指南,该变异可能致病。结论该ADOA家系患者表现为青少年时期发病的双眼视神经萎缩,左眼为主;OPA 1基因c.676C>T变异可能为该ADOA家系致病变异位点,该变异位点为首次报道。 展开更多
关键词 常染色体显性遗传性视神经萎缩 家系 表型 OPA1基因 基因突变
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基于突变理论的隔水岩体失稳分析及安全厚度计算
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作者 方林 龚晟 +1 位作者 王桂林 余浩 《中国安全科学学报》 CAS CSCD 北大核心 2024年第3期76-83,共8页
为了保障岩溶突水隧道施工和运营安全,基于弹性梁模型,应用突变理论建立岩溶突水顶板在动力扰动下失稳的双尖点突变模型;综合考虑围岩性质、静水压力、动力扰动等因素,分析岩溶突水隧道顶板的失稳机制和破坏条件,建立其失稳突变的判别方... 为了保障岩溶突水隧道施工和运营安全,基于弹性梁模型,应用突变理论建立岩溶突水顶板在动力扰动下失稳的双尖点突变模型;综合考虑围岩性质、静水压力、动力扰动等因素,分析岩溶突水隧道顶板的失稳机制和破坏条件,建立其失稳突变的判别方程,并采用Matlab软件编程,求解顶板的最小安全厚度;同时,为了避免当静水压力过大时,突变理论公式的不合理性,单独计算仅在静水压力的情况下的最小安全厚度,并取两者计算值中的更大值。结果表明:隔水岩体是否保持稳定是由岩体内外因素共同决定的;岩体跨度越长,岩体最小安全厚度越大;岩体弹性模量越大,岩体最小安全厚度越小。在振动频率一定时,爆破荷载越大,岩体最小安全厚度越大;在爆破荷载的大小一定时,爆破振动的频率越大,岩体最小安全厚度越小;静水压力越大,岩体最小安全厚度越大。该岩溶突水隧道顶板安全厚度计算方法具有可行性与较高的准确性。 展开更多
关键词 突变理论 隔水岩体失稳 安全厚度 动荷载 静水压力
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多策略融合改进的自适应蜉蝣算法 被引量:3
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作者 蒋宇飞 许贤泽 +1 位作者 徐逢秋 高波 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2024年第4期1416-1426,共11页
为改进蜉蝣算法全局搜索能力较差、种群多样性较小和自适应能力弱等问题,提出一种多策略融合改进的自适应蜉蝣算法(MIMA)。采用Sin混沌映射初始化蜉蝣种群,使种群能够均匀分布在解空间中,提高初始种群质量,增强全局搜索能力;引入Tent混... 为改进蜉蝣算法全局搜索能力较差、种群多样性较小和自适应能力弱等问题,提出一种多策略融合改进的自适应蜉蝣算法(MIMA)。采用Sin混沌映射初始化蜉蝣种群,使种群能够均匀分布在解空间中,提高初始种群质量,增强全局搜索能力;引入Tent混沌映射和高斯变异对种群个体进行调节,增加种群多样性的同时调控种群密度,增强局部最优逃逸能力;引入不完全伽马函数,重构自适应动态调节的重力系数,建立全局搜索和局部开发能力之间更好的平衡,进而提升算法收敛精度,有利于提高全局搜索能力;采用随机反向学习(ROBL)策略,增强全局搜索能力,提高收敛速度并增强稳定性。利用经典测试函数集进行算法对比,并利用Wilcoxon秩和检验分析算法的优化效果,证明改进的有效性和可靠性。实验结果表明:所提算法与其他算法相比,寻优精度、收敛速度、稳定性都取得了较大提升。 展开更多
关键词 蜉蝣算法 混沌映射 高斯变异 自适应动态调节 随机反向学习
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家族性高胆固醇血症一家系基因突变分析和临床治疗
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作者 朱业 顾翔 +1 位作者 朱华 刘佳 《中国动脉硬化杂志》 CAS 2024年第1期24-30,共7页
[目的]总结1例家族性高胆固醇血症(FH)家系的基因突变分析和临床治疗方案。[方法]先证者因“反复气喘伴胸痛4个月,加重2天”入院,血浆低密度脂蛋白胆固醇(LDLC)异常升高,且早发冠心病,对先证者进行全外显子测序和载脂蛋白E(ApoE)、对氧... [目的]总结1例家族性高胆固醇血症(FH)家系的基因突变分析和临床治疗方案。[方法]先证者因“反复气喘伴胸痛4个月,加重2天”入院,血浆低密度脂蛋白胆固醇(LDLC)异常升高,且早发冠心病,对先证者进行全外显子测序和载脂蛋白E(ApoE)、对氧磷酶1(PON1)、前蛋白转化酶枯草溶菌素9(PCSK9)等位点进行测序分析,针对可疑致病突变在家系成员中进行检测,对先证者及其父亲进行了冠状动脉介入治疗和降脂治疗。[结果]先证者、其父亲和其儿子在低密度脂蛋白受体(LDLR)基因中均检出了6个突变位点,分别为c.191+13G>A(rs200621482)、c.1598G>T(rs200427089)、c.883T>G(rs553235458)、c.3536A>G(rs201300867)、c.2215+6G>A(rs540060615)、c.162+5A>T(rs146596406)。这3例患者的6个位点均为杂合突变。3例患者的ApoE基因型结果如下:先证者及其儿子的ApoE基因型均为ε3/ε3型,蛋白表型为E3(ApoE2位点为CC型,ApoE4位点为TT型);其父亲的ApoE基因型为ε2/ε3型,蛋白表型为E2(ApoE2位点为CT型,ApoE4位点为TT型)。3例患者的PON1(A575G,rs662)位点基因型均为AG型,3例患者的PCSK9基因型为GG、CC、CC、GG型。基于该家系遗传学检测结果,给予先证者及其父亲个体化的降脂治疗方案,阿托伐他汀钙与依折麦布联合PCSK9抑制剂,且先证者及其父亲成功行冠状动脉介入治疗术,随访两年LDLC控制较好,未出现药物不良反应。[结论]本研究中该家系患者的LDLR基因均发现6个位点突变,其中LDLR c.191+13G>A、c.162+5A>T在国内尚未见报道,丰富了中国人群的LDLR基因突变谱。本研究有利于阐明FH的发病机制,进一步指导FH患者的临床治疗。 展开更多
关键词 家族性高胆固醇血症 家系 基因突变
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F12基因p.Gly175Cys和p.Gly542Ser复合杂合突变导致的遗传性凝血因子Ⅻ缺陷症的家系分析
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作者 程晓丽 杨婷 +4 位作者 杨柳 辛毅娟 何睦 朱琳 刘家云 《中国实验血液学杂志》 CAS CSCD 北大核心 2024年第3期862-867,共6页
目的:分析1例遗传性凝血因子Ⅻ(FⅫ)缺陷症家系的临床表型和基因突变情况,并探讨其分子致病机制。方法:凝固法检测活化部分凝血活酶时间和FⅫ活性;ELISA方法检测FⅫ抗原;Sanger测序法测定F12基因所有外显子及侧翼序列;ClustalX-2.1-win... 目的:分析1例遗传性凝血因子Ⅻ(FⅫ)缺陷症家系的临床表型和基因突变情况,并探讨其分子致病机制。方法:凝固法检测活化部分凝血活酶时间和FⅫ活性;ELISA方法检测FⅫ抗原;Sanger测序法测定F12基因所有外显子及侧翼序列;ClustalX-2.1-win、PROVEAN及Swiss-Pdb Viewer软件分析突变位点氨基酸的保守性、突变氨基酸是否为有害突变及该位点发生突变后对蛋白质结构的影响。结果:先证者活化部分凝血活酶时间延长为71.3 s,FⅫ活性和FⅫ抗原分别降低为5%和6%;其F12基因第7和14外显子分别存在c.580G>T和c.1681G>A杂合错义突变,导致p.Gly175Cys和p.Gly542Ser;先证者父亲携带p.Gly175Cys杂合错义突变;先证者母亲、弟弟和女儿携带p.Gly542Ser杂合错义突变。软件分析结果表明Gly175和Gly542均保守,p.Gly175Cys和p.Gly542Ser为有害突变,突变发生后相应位点会对蛋白质局部结构产生影响。结论:p.Gly175Cys和p.Gly542Ser复合杂合突变是先证者家系遗传性FⅫ缺陷症的分子发病机制,其中p.Gly175Cys为国际上首次发现的新突变。 展开更多
关键词 凝血因子Ⅻ 错义突变 家系 遗传性FⅫ缺陷症
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动态对比增强磁共振成像及弥散加权成像参数与乳腺癌肿瘤突变负荷的相关性
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作者 张崇杰 杨珏红 +1 位作者 王俊波 郝晓宁 《分子影像学杂志》 2024年第4期414-419,共6页
目的探讨动态对比增强磁共振成像(DCE-MRI)及弥散加权成像(DWI)参数与乳腺癌肿瘤突变负荷(TMB)的相关性,评价DCE-MRI及DWI在乳腺癌免疫治疗中的潜在价值。方法回顾性分析山西医科大学附属运城医院暨第八临床医学院2019~2021年共100例乳... 目的探讨动态对比增强磁共振成像(DCE-MRI)及弥散加权成像(DWI)参数与乳腺癌肿瘤突变负荷(TMB)的相关性,评价DCE-MRI及DWI在乳腺癌免疫治疗中的潜在价值。方法回顾性分析山西医科大学附属运城医院暨第八临床医学院2019~2021年共100例乳腺癌患者的临床资料和术前MRI检查结果。根据TMB值的中位数(5.4/Mb),将100例患者分为TMB高表达组(TMB≥5.4/Mb,n=28)和TMB低表达组(TMB<5.4/Mb,n=72)。提取DCE-MRI及DWI的影像特征,计算表观扩散系数(ADC)和动态增强曲线类型等参数。采用高通量测序技术检测肿瘤组织中的基因突变情况,计算TMB值。分析DCE-MRI及DWI参数与TMB值之间的相关性,以及与乳腺癌病理指标[雌激素受体、孕激素受体、人表皮生长因子受体2、Ki67]之间的关系。采用单因素和多因素Logistic回归分析筛选影响TMB值的独立危险因素。结果DCE-MRI及DWI参数中,ADC值、动态增强曲线类型、峰值信号强度、时间-信号强度曲线斜率等与TMB值呈负相关关系(P<0.05),而峰时、时间-信号强度曲线下面积等与TMB值呈正相关关系(P<0.05)。乳腺癌病理指标中,雌激素受体、孕激素受体、人表皮生长因子受体2、Ki67的表达与TMB值均无相关性(P>0.05)。多因素Logistic回归分析显示,ADC值、动态增强曲线类型和峰时是影响TMB值的独立危险因素。结论DCEMRI及DWI参数与乳腺癌TMB值存在显著相关性,可作为评估乳腺癌免疫治疗效果的辅助手段。 展开更多
关键词 乳腺癌 磁共振成像 动态增强 扩散加权 肿瘤突变负荷
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